1.5 million square feet, one big mystery tenant

Vulcan, Paul Allen's development firm, has announced a twist in its plans to make over South Lake Union: roughly 1.5 million square feet of new office buildings for a single tenant, a large employer who remains unnamed.

The tenant would occupy new buildings — some as tall as 160 feet if Vulcan has its way — covering six blocks in the neighborhood.

Vulcan executives wouldn't disclose the identity of the tenant. "We're not ready to announce the tenant at this point," said Sharon Coleman, Vulcan's development manager.

Amazon.com is rumored to be the tenant, joining Microsoft and Group Health as the latest employers coming to the area. But officials at Amazon, Vulcan and City Hall won't confirm that.

Vulcan's newest project would be built in three phases and completed in 2011. It would stretch from Mercer Street, near Lake Union, to John Street, a block from Denny Way.

It would not be a "sterile campus," Coleman said. Instead, its character would be "scrappy, funky and cool" and Vulcan would use three different architects to give the buildings a diverse look, she said.

The first four buildings, which would be closer to the lake, would be five-story structures about 80 feet tall. The last two would be 12-story buildings up to 160 feet. Current height limits range from 65 to 85 feet in the area.

Mayor Greg Nickels plans to propose sweeping zoning changes for the South Lake Union area. Nickels wants developers to pay for public benefits, such as affordable housing, in exchange for permission to build taller.

But Coleman said Vulcan couldn't wait for that larger zoning proposal because of the needs of its potential tenant.

"We need to move. We don't have time to wait for the upzone. We need a guarantee we can get the height by the end of the year" for the two 12-story buildings, Coleman said.

Amazon employees in Seattle are mostly spread among three office buildings near downtown: the Columbia Center tower, the Union Station development and the historic Pacific Medical Center on Beacon Hill. The company's leases at the PacMed building and Columbia Center expire in 2010.

If Vulcan isn't allowed to build taller buildings, the project would "sprawl" to the west side of Westlake Avenue North, Coleman said.

Nickels will send legislation to the City Council in the next week seeking the height change, said Deputy Mayor Tim Ceis.

In return for the extra height on two blocks, Vulcan would contribute approximately $5 million for affordable housing, said Ceis and Lyn Tangen, Vulcan's director of government and community relations. The amount would be determined by a formula similar to what the city uses for downtown office buildings that exceed height limits.

Vulcan would also agree to develop energy-efficient buildings and implement an aggressive transportation plan that would require that most of the employees in the new buildings not bring their cars to work.

The new buildings would be next to the South Lake Union streetcar line scheduled to open in December. Vulcan hopes its new tenant's employees will live in new apartment and condo buildings the company is developing in the area.

"This potential tenant does a lot of biking and walking," Coleman said.

Lloyd Douglas, president of the Cascade Neighborhood Council, said his group learned of the new Vulcan projects at a Thursday night meeting.

"This is the first we've seen of it," Douglas said. The Cascade neighborhood is part of the larger South Lake Union area.

Douglas said he hopes the required affordable housing is built in his neighborhood. "If we're going to live with all the height and stuff, we might as well enjoy all that's being generated by it," he said.

Vulcan announced the new projects at the Thursday meeting held to promote a community "vision" for Lower Queen Anne and South Lake Union.

That vision — of more dense development, housing for a range of incomes, and improved transit — has been endorsed by 37 community, business and advocacy groups. Endorsers include Sharon Lee, executive director of the Low Income Housing Institute; Dick Wagner, founding director of the Center for Wooden Boats; and Martin Kaplan, a member of the Seattle Planning Commission.

"There's going to be a lot more interaction with the community. This is just a start," Vulcan's Coleman said.

Times reporter Amy Martinez contributed to this report. Bob Young: 206-464-2174 or byoung@seattletimes.com